Publications by authors named "Seung Hyun Moon"

18 Publications

  • Page 1 of 1

Clinical and Economic Burden of Multiple Double-Stranded DNA Viral Infections after Allogeneic Hematopoietic Cell Transplantation.

Transplant Cell Ther 2022 Jun 25. Epub 2022 Jun 25.

Knight Cancer Institute, Oregon Health & Science University, Portland, Oregon.

Conditioning regimens for allogeneic hematopoietic cell transplantation (allo-HCT) are immunosuppressive and increase the risk for reactivation of and infection with double-stranded DNA (dsDNA) viruses, which contribute to morbidity and mortality after allo-HCT. This retrospective observational study evaluated the association of dsDNA viral infections with clinical outcomes, health resource utilization (HRU), and health care reimbursement after allo-HCT. Patients who underwent allo-HCT between 2012 and 2017 were identified from a US open-source claims database (Decision Resource Group Real-World Evidence Data Repository; n = 13,363) and categorized according to the presence or absence of dsDNA viral infection, defined as having ≥1 diagnosis code for cytomegalovirus (CMV), adenovirus (AdV), human herpesvirus 6 (HHV-6), or BK virus (BKV)/Epstein-Barr virus (EBV)/John Cunningham virus (JCV) (grouped together given a lack of specific diagnoses codes) within 1 year after allo-HCT. Only first allo-HCT data were used in patients who underwent multiple procedures. Study outcomes included clinical outcomes (eg, time to all-cause mortality, new diagnosis of renal impairment), HRU (hospital and intensive care unit length of stay [LOS], readmission rates), and health care reimbursement (total, inpatient, and outpatient costs as reported reimbursements from insurance claims). For all outcomes, patients were stratified by the presence/absence of any dsDNA viral infection and number (none, 1, 2, or ≥3) and type(s) of infection. The effect of graft-versus-host disease (GVHD) was assessed as well. Twenty-nine percent of patients were diagnosed with CMV, 13% with BKV/EBV/JCV, 5% with AdV, and 4% with HHV-6 in the year following their first allo-HCT. A single dsDNA viral infection was documented in 30% of individuals, 2 in 8%, and ≥3 in 2%. Patients with no viral infections had an overall hospital LOS (index hospitalization plus readmissions) of 41.3 days and a total health care reimbursement of $266,345. These numbers increased for every additional viral infection, regardless of the presence or absence of GVHD; the overall hospital LOS was 61.4 days and total healthcare reimbursement was $431,614 in patients with 1 viral infection, 77.0 days and $639,097 in patients with 2 viral infections, and 103.3 days and $964,378 in patients with ≥3 viral infections. An increase in the number of dsDNA viral infections was associated with a significantly higher adjusted hazard of all-cause mortality (1 versus 0 dsDNA viral infections: hazard ratio [HR], 1.5; [95% confidence interval (CI), 1.3 to 1.6]; 2 versus 0: HR, 2.0 [95% CI, 1.7 to 2.3]; ≥3 versus 0: HR, 2.4 [95% CI, 1.8 to 3.3]) and a significantly higher incidence of new diagnosis of renal impairment, regardless of the presence of GVHD (35% of patients with ≥3 infections, 31% of patients with 2 infections, 26% of patients with 1 infection, and 19% of patients with no infection). These results indicate that more directed prevention and treatment strategies for dsDNA viral infections could substantially improve clinical outcomes and reduce HRU.
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http://dx.doi.org/10.1016/j.jtct.2022.06.016DOI Listing
June 2022

Economic and clinical burden associated with respiratory viral infections after allogeneic hematopoietic cell transplant in the United States.

Transpl Infect Dis 2022 Aug 1;24(4):e13866. Epub 2022 Jun 1.

Certara, New York, New York, USA.

Background: Allogeneic hematopoietic cell transplant (allo-HCT) recipients are at increased risk for respiratory viral infections (RVIs), which invoke substantial morbidity and mortality. Limited effective antiviral options and drug resistance often hamper successful RVI treatment, creating additional burden for patients and the health care system.

Methods: Using an open-source health care claims database, we examined differences in clinical outcomes, health resource utilization, and total reimbursements during the 1-year period following allo-HCT in patients with and without any RVI infection (respiratory syncytial virus, influenza, parainfluenza virus, and human metapneumovirus). RVIs were diagnosed at any time ≤1 year after allo-HCT and identified by International Classification of Disease codes. Analyses were stratified by the presence or absence of acute or chronic graft-versus-host disease (GVHD).

Results: The study included 13 363 allo-HCT patients, 1368 (10.2%) of whom had a diagnostic code for any RVI. A higher proportion of patients with any RVI had pneumonia ≤1 year after allo-HCT compared to patients without any RVI, with or without GVHD. Patients with any RVI had higher all-cause mortality risk, longer length of post-allo-HCT hospital stay, higher readmission rate, and higher number of hospital days after allo-HCT compared to patients without the infection (all p < .05). Total unadjusted median reimbursements were higher for those with any RVI and each specific RVI assessed than those without the specific infection, with or without GVHD.

Conclusion: Allo-HCT patients with RVIs had significantly worse clinical outcomes and increased health resource utilization and reimbursements during the year following allo-HCT, with or without GVHD.
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http://dx.doi.org/10.1111/tid.13866DOI Listing
August 2022

Economic and Clinical Burden of Virus-Associated Hemorrhagic Cystitis in Patients Following Allogeneic Hematopoietic Stem Cell Transplantation in the United States.

Transplant Cell Ther 2021 06 26;27(6):505.e1-505.e9. Epub 2021 Feb 26.

Memorial Sloan Kettering Cancer Center, New York, New York.

Hemorrhagic cystitis (HC) caused by viral infections such as BK virus, cytomegalovirus, and/or adenovirus after allogeneic hematopoietic stem cell transplantation (allo-HCT) causes morbidity and mortality, affects quality of life, and poses a substantial burden to the health care system. At present, HC management is purely supportive, as there are no approved or recommended antivirals for virus-associated HC. The objective of this retrospective observational study was to compare the economic burden, health resource utilization (HRU), and clinical outcomes among allo-HCT recipients with virus-associated HC to those without virus-associated HC using a large US claims database. Claims data obtained from the Decision Resources Group Real-World Evidence Data Repository were used to identify patients with first (index) allo-HCT procedure from January 1, 2012, through December 31, 2017. Outcomes were examined 1 year after allo-HCT and included total health care reimbursements, HRU, and clinical outcomes for allo-HCT patients with virus-associated HC versus those without. Further, a generalized linear model was used to determine adjusted reimbursements stratified by the presence or absence of any acute or chronic graft-versus-host disease (GVHD) after adjusting for age, health plan, underlying disease, stem cell source, number of comorbidities, baseline reimbursements, and follow-up time. Of 13,363 allo-HCT recipients, 759 (5.7%) patients met the prespecified criteria for virus-associated HC. Total unadjusted mean reimbursement was $632,870 for patients with virus-associated HC and $340,469 for patients without virus-associated HC. In a multivariable model, after adjusting for confounders, the adjusted reimbursements were significantly higher for virus-associated HC patients with and without GVHD compared to patients without virus-associated HC (P < .0001). Patients with virus-associated HC stayed 7.9 additional days in the hospital (P < .0001) and 6.1 additional days (P = .0009) in the intensive care unit (ICU) for the index hospitalization, as compared to patients without virus-associated HC. The hospital readmission rate was higher for allo-HCT patients with versus without virus-associated HC (P < .0001), resulting in 12.9 more days in the hospital (P < .0001) and 7.3 more days in the ICU (P < .0001) after the index hospitalization. Among patients with GVHD, those with virus-associated HC had significantly higher all-cause mortality as compared to those without virus-associated HC (23.2% versus 18.4%; P = .0035). In an adjusted analysis, patients with virus-associated HC had a significantly higher risk of mortality, regardless of the presence of GVHD. When stratified by GVHD, there were no significant differences in the baseline risk for renal impairment; virus-associated HC was associated with increased risk for renal impairment in the follow-up period in patients with or without GVHD (P < .0001 for both). After allo-HCT, patients with virus-associated HC have significantly higher health care reimbursements and HRU, with worse clinical outcomes, including renal impairment, irrespective of the presence of GVHD and significantly higher all-cause mortality in the presence of GVHD. Our results highlight the unmet clinical need for effective strategies to prevent and treat virus-associated HC in HCT recipients that may also reduce costs among these patients.
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http://dx.doi.org/10.1016/j.jtct.2021.02.021DOI Listing
June 2021

Preparation of Pyridylamido Hafnium Complexes for Coordinative Chain Transfer Polymerization.

Polymers (Basel) 2020 May 11;12(5). Epub 2020 May 11.

Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea.

The pyridylamido hafnium complex () discovered at Dow is a flagship catalyst among postmetallocenes, which are used in the polyolefin industry for PO-chain growth from a chain transfer agent, dialkylzinc. In the present work, with the aim to block a possible deactivation process in prototype compound , the corresponding derivatives were prepared. A series of pyridylamido Hf complexes were prepared by replacing the 2,6-diisopropylphenylamido part in with various 2,6-RCHN-moieties (R = cycloheptyl, cyclohexyl, cyclopentyl, 3-pentyl, ethyl, or Ph) or by replacing 2-iPrCHC(H)- in with the simple PhC(H)-moiety. The isopropyl substituent in the 2-iPrCHC(H)-moiety influences not only the geometry of the structures (revealed by X-ray crystallography), but also catalytic performance. In the complexes bearing the 2-iPrCHC(H)-moiety, the chelation framework forms a plane; however, this framework is distorted in the complexes containing the PhC(H)-moiety. The ability to incorporate α-olefin decreased upon replacing 2-iPrCHC(H)-with the PhC(H)-moiety. The complexes carrying the 2,6-di(cycloheptyl)phenylamido or 2,6-di(cyclohexyl)phenylamido moiety (replacing the 2,6-diisopropylphenylamido part in ) showed somewhat higher activity with greater longevity than did prototype catalyst .
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http://dx.doi.org/10.3390/polym12051100DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7285347PMC
May 2020

Spatiotemporal Approaches for Quality Control and Error Correction of Atmospheric Data through Machine Learning.

Comput Intell Neurosci 2020 11;2020:7980434. Epub 2020 Mar 11.

Department of Computer Science, Kwangwoon University, 20 Kwangwoon-ro, Nowon-gu, Seoul 01897, Republic of Korea.

We propose three quality control (QC) techniques using machine learning that depend on the type of input data used for training. These include QC based on time series of a single weather element, QC based on time series in conjunction with other weather elements, and QC using spatiotemporal characteristics. We performed machine learning-based QC on each weather element of atmospheric data, such as temperature, acquired from seven types of IoT sensors and applied machine learning algorithms, such as support vector regression, on data with errors to make meaningful estimates from them. By using the root mean squared error (RMSE), we evaluated the performance of the proposed techniques. As a result, the QC done in conjunction with other weather elements had 0.14% lower RMSE on average than QC conducted with only a single weather element. In the case of QC with spatiotemporal characteristic considerations, the QC done via training with AWS data showed performance with 17% lower RMSE than QC done with only raw data.
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http://dx.doi.org/10.1155/2020/7980434DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7086422PMC
December 2020

Polystyrene Chain Growth Initiated from Dialkylzinc for Synthesis of Polyolefin-Polystyrene Block Copolymers.

Polymers (Basel) 2020 Mar 2;12(3). Epub 2020 Mar 2.

Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea.

Polyolefins (POs) are the most abundant polymers. However, synthesis of PO-based block copolymers has only rarely been achieved. We aimed to synthesize various PO-based block copolymers by coordinative chain transfer polymerization (CCTP) followed by anionic polymerization in one-pot via conversion of the CCTP product (polyolefinyl)Zn to polyolefinyl-Li. The addition of 2 equiv -BuLi to (1-octyl)Zn (a model compound of (polyolefinyl)Zn) and selective removal or decomposition of (Bu)Zn by evacuation or heating at 130 °C afforded 1-octyl-Li. Attempts to convert (polyolefinyl)Zn to polyolefinyl-Li were unsuccessful. However, polystyrene (PS) chains were efficiently grown from (polyolefinyl)Zn; the addition of styrene monomers after treatment with -BuLi and pentamethyldiethylenetriamine (PMDTA) in the presence of residual olefin monomers afforded PO--PSs. Organolithium species that might be generated in the pot of -BuLi, PMDTA, and olefin monomers, i.e., [MeNCHCHN(Me)CHCHN(Me)CHLi, MeNCHCHN(Me)Li·(PMDTA), pentylallyl-Li⋅(PMDTA)], as well as PhLi⋅(PMDTA), were screened as initiators to grow PS chains from (1-hexyl)Zn, as well as from (polyolefinyl)Zn. Pentylallyl-Li⋅(PMDTA) was the best initiator. The values increased substantially after the styrene polymerization with some generation of homo-PSs (27-29%). The values of the extracted homo-PS suggested that PS chains were grown mainly from polyolefinyl groups in [(polyolefinyl)(pentylallyl)Zn][Li⋅(PMDTA)] formed by pentylallyl-Li⋅(PMDTA) acting onto (polyolefinyl)Zn.
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http://dx.doi.org/10.3390/polym12030537DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7182881PMC
March 2020

Design, construction, and operation of an 18 T 70 mm no-insulation (RE)BaCuO magnet for an axion haloscope experiment.

Rev Sci Instrum 2020 Feb;91(2):023314

Electrical and Computer Engineering Department, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, South Korea.

We report the design, construction, and operation results of an 18 T 70 mm cold-bore high temperature superconductor (HTS) no-insulation (NI) magnet, which is developed for an axion haloscope experiment. The magnet consists of 44 double-pancake coils wound with multi-width and multi-thickness REBaCuO (RE = rare earth) tapes. Owing to the NI feature, the magnet is highly compact; is 162 mm in outer diameter and 476 mm tall; and provides an environment of 0.22 T m within the cold-bore target space of 66 mm in diameter and 200 mm in length. After an initial performance test at SuNAM Co. Ltd., the magnet was installed at the Center for Axion and Precision Physics Research (CAPP) of the Institute for Basic Science in Daejeon, South Korea, in August 2017. The magnet has been successfully operating at the CAPP since then, except for maintenance in October 2018. The magnet may represent the first high field HTS user magnet that experienced long-term operation of over one year.
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http://dx.doi.org/10.1063/1.5124432DOI Listing
February 2020

Strategy toward the fabrication of ultrahigh-resolution micro-LED displays by bonding-interface-engineered vertical stacking and surface passivation.

Nanoscale 2019 Dec;11(48):23139-23148

Information and Electronics Research Institute, Korea Advanced Institute of Science and Technology (KAIST), Daehak-ro 291, Yuseong-gu, Daejeon 34141, Republic of Korea.

In this study, we proposed a strategy to fabricate vertically stacked subpixel (VSS) micro-light-emitting diodes (μ-LEDs) for future ultrahigh-resolution microdisplays. At first, to vertically stack the LED with different colors, we successfully adopted a bonding-interface-engineered monolithic integration method using SiO2/SiNx distributed Bragg reflectors (DBRs). It was found that an intermediate DBR structure could be used as the bonding layer and color filter, which could reflect and transmit desired wavelengths through the bonding interface. Furthermore, the optically pumped μ-LED array with a pitch of 0.4 μm corresponding to the ultrahigh-resolution of 63 500 PPI could be successfully fabricated using a typical semiconductor process, including electron-beam lithography. Compared with the pick-and-place strategy (limited by machine alignment accuracy), the proposed strategy leads to the fabrication of significantly improved high-density μ-LEDs. Finally, we systematically investigated the effects of surface traps using time-resolved photoluminescence (TRPL) and two-dimensional simulations. The obtained results clearly demonstrated that performance improvements could be possible by employing optimal passivation techniques by diminishing the pixel size for fabricating low-power and highly efficient microdisplays.
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http://dx.doi.org/10.1039/c9nr04423jDOI Listing
December 2019

Tobramycin Promotes Melanogenesis by Upregulating p38 MAPK Protein Phosphorylation in B16F10 Melanoma Cells.

Antibiotics (Basel) 2019 Sep 5;8(3). Epub 2019 Sep 5.

Department of Chemistry and Cosmetics, Jeju National University, Jeju 63243, Korea.

Tobramycin is an aminoglycoside-based natural antibiotic derived from , which is primarily used for Gram-negative bacterial infection treatment. Although tobramycin has been utilized in clinical practice for a long time, it has exhibited several side effects, leading to the introduction of more effective antibiotics. Therefore, we conducted our experiments focusing on new possibilities for the clinical use of tobramycin. How tobramycin affects skin melanin formation is unknown. This study used B16F10 melanoma cells to assess the effect of tobramycin on melanin production. After cytotoxicity was assessed by MTT assay, melanin content and tyrosinase activity analyses revealed that tobramycin induces melanin synthesis in B16F10 cells. Next, Western blot analyses were performed to elucidate the mechanism by which tobramycin increases melanin production; phosphorylated p38 protein expression was upregulated. Protein inhibitors have been used to elucidate the mechanism of tobramycin. Kanamycin A and B are structurally similar to tobramycin, and 2-DOS represents the central structure of these antibiotics. The effects of these substances on melanogenesis were evaluated. Kanamycin A reduced melanin production, whereas kanamycin B and 2-DOS had no effect. Overall, our data indicated that tobramycin increases melanin production by promoting p38 protein phosphorylation in B16F10 melanoma cells.
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http://dx.doi.org/10.3390/antibiotics8030140DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6783951PMC
September 2019

A Case of Idiopathic Hemihypertrophy with Hemihypertrichosis.

Int J Trichology 2018 Nov-Dec;10(6):292-293

Department of Dermatology, Busan Paik Hospital, College of Medicine, Inje University, Busan, Korea.

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http://dx.doi.org/10.4103/ijt.ijt_55_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369641PMC
February 2019

Primary Cutaneous Nocardiosis Caused by .

Ann Dermatol 2017 Aug 21;29(4):471-475. Epub 2017 Jun 21.

Department of Dermatology, Kosin University College of Medicine, Busan, Korea.

species are aerobic, gram-positive, filamentous, partially acid-fast actinomycetes which are found worldwide in soil and decaying organic plant matter. When they infect human beings, they generally enter through the respiratory tract and then disseminate systemically. Rarely has a primary infection occurred as the result of direct inoculation. Isolation of from clinical specimens and identification of species are difficult. But, with the introduction of new genetic technologies, reports of novel species of have increased. We describe a case of cutaneous nocardiosis caused by in an 87-year-old woman who was diagnosed by bacterial culture and 16S ribosomal RNA sequencing. has been described as a new species. This report describes the first clinical isolate of from a skin specimen in Korea.
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http://dx.doi.org/10.5021/ad.2017.29.4.471DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5500713PMC
August 2017

Identification of Molecular Signatures from Different Vaccine Adjuvants in Chicken by Integrative Analysis of Microarray Data.

Asian-Australas J Anim Sci 2016 Jul 6;29(7):1044-51. Epub 2015 Apr 6.

Department of Animal Biotechnology, Chonbuk National University, Jeonju 561-756, Korea.

The present study compared the differential functions of two groups of adjuvants, Montanide incomplete Seppic adjuvant (ISA) series and Quil A, cholesterol, dimethyl dioctadecyl ammonium bromide, and Carbopol (QCDC) formulations, in chicken by analyzing published microarray data associated with each type of vaccine adjuvants. In the biological function analysis for differentially expressed genes altered by two different adjuvant groups, ISA series and QCDC formulations showed differential effects when chickens were immunized with a recombinant immunogenic protein of Eimeria. Among the biological functions, six categories were modified in both adjuvant types. However, with respect to "Response to stimulus", no biological process was modified by the two adjuvant groups at the same time. The QCDC adjuvants showed effects on the biological processes (BPs) including the innate immune response and the immune response to the external stimulus such as toxin and bacterium, while the ISA adjuvants modified the BPs to regulate cell movement and the response to stress. In pathway analysis, ISA adjuvants altered the genes involved in the functions related with cell junctions and the elimination of exogenous and endogenous macromolecules. The analysis in the present study could contribute to the development of precise adjuvants based on molecular signatures related with their immunological functions.
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http://dx.doi.org/10.5713/ajas.14.0923DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4932582PMC
July 2016

Cutaneous and Systemic Plasmacytosis Associated with Renal Amyloidosis.

Ann Dermatol 2015 Dec 7;27(6):759-62. Epub 2015 Dec 7.

Department of Dermatology, Severance Hospital & Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea.

Cutaneous and systemic plasmacytosis (CSP) is a rare disorder of unknown etiology characterized by cutaneous polyclonal plasma cell infiltrates associated with various extracutaneous involvement and polyclonal hypergammaglobulinemia. Here, we report on a 54-year-old male patient with chronic renal insufficiency who presented with disseminated reddish-brown macules and plaques on the face and trunk. In our evaluation, he was found to have lymphadenopathy, polyclonal hypergammaglobulinemia; benign plasma cell infiltration involving the skin, bone marrow, and retroperitoneal area; and renal amyloidosis. To the best of our knowledge, this is the first reported case of CSP associated with renal amyloidosis.
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http://dx.doi.org/10.5021/ad.2015.27.6.759DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4695432PMC
December 2015

Ultra-high performance, high-temperature superconducting wires via cost-effective, scalable, co-evaporation process.

Sci Rep 2014 Apr 22;4:4744. Epub 2014 Apr 22.

Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.

Long-length, high-temperature superconducting (HTS) wires capable of carrying high critical current, Ic, are required for a wide range of applications. Here, we report extremely high performance HTS wires based on 5 μm thick SmBa2Cu3O7--δ (SmBCO) single layer films on textured metallic templates. SmBCO layer wires over 20 meters long were deposited by a cost-effective, scalable co-evaporation process using a batch-type drum in a dual chamber. All deposition parameters influencing the composition, phase, and texture of the films were optimized via a unique combinatorial method that is broadly applicable for co-evaporation of other promising complex materials containing several cations. Thick SmBCO layers deposited under optimized conditions exhibit excellent cube-on-cube epitaxy. Such excellent structural epitaxy over the entire thickness results in exceptionally high Ic performance, with average Ic over 1,000 A/cm-width for the entire 22 meter long wire and maximum Ic over 1,500 A/cm-width for a short 12 cm long tape. The Ic values reported in this work are the highest values ever reported from any lengths of cuprate-based HTS wire or conductor.
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http://dx.doi.org/10.1038/srep04744DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3994444PMC
April 2014

The evaporative drying of sludge by immersion in hot oil: Effects of oil type and temperature.

J Hazard Mater 2010 Jun 28;178(1-3):483-8. Epub 2010 Jan 28.

Department of Environmental Engineering, Hanbat National University, San 16-1 Duckmyung-dong, Yusung-gu, Daejeon 305-719, Republic of Korea.

We investigated the evaporative drying by immersion in hot oil (EDIHO) method for drying sludge. This involved heating oil to a temperature higher than that needed for moisture to be evaporated from the sludge by turbulent heat and mass transfer. We fry-dried sewage and leather plant sludge for 10 min in each of four different oils (waste engine, waste cooking, refined waste, and B-C heavy) and three different temperatures (140 degrees C, 150 degrees C, and 160 degrees C). Drying efficiency was found to be greater for higher temperatures. However, giving consideration to energy efficiency we suggest that the optimal temperature for fry-drying sludge is 150 degrees C. At 150 degrees C, the water content of sewage sludge reduced from 78.9% to between 1.5% (with waste cooking oil) and 3.8% (with waste engine oil). The reduction in water content for leather plant sludge fry-dried at 150 degrees C was from 81.6% to between 1% (with waste cooking oil) and 6.5% (with refined waste oil). The duration of the constant rate-drying period was also influenced by the type of oil used: refined waste oil>waste engine oil>B-C heavy oil>waste cooking oil. The duration at 150 degrees C with waste cooking oil was 3 min for sewage sludge and 2 min for leather plant sludge. It is likely that the drying characteristics of oil are influenced by its thermal properties, including its specific heat, and molecular weight.
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http://dx.doi.org/10.1016/j.jhazmat.2010.01.107DOI Listing
June 2010

A study on the dewatering of industrial waste sludge by fry-drying technology.

J Hazard Mater 2009 Aug 20;168(1):445-50. Epub 2009 Feb 20.

Department of Environmental Engineering, Hanbat National University, Daejeon, Republic of Korea.

In sludge treatment, drying sludge using typical technology with high water content to a water content of approximately 10% is always difficult because of adhesive characteristics of sludge. Many methods have been applied, including direct and indirect heat drying, but these approaches of reducing water content to below 40% after drying is very inefficient in energy utilization of drying sludge. In this study, fry-drying technology with a high heat transfer coefficient of approximately 500 W/m(2) degrees C was used to dry industrial wastewater sludge. Also waste oil was used in the fry-drying process, and because the oil's boiling point is between 240 and 340 degrees C and the specific heat is approximately 60% of that of water. In the fry-drying system, the sludge is input by molding it into a designated form after heating the waste oil at temperatures between 120 and 170 degrees C. At these temperatures, the heated oil rapidly evaporates the water contained in the sludge, leaving the oil itself. After approximately 10 min, the water content of the sludge was less than 10%, and its heating value surpassed 5300 kcal/kg. Indeed, this makes the organic sludge appropriate for use as a solid fuel. The wastewater sludge used in this study was the designated waste discharged from chemical, leather and plating plants. These samples varied in characteristics, especially with regard to heavy metal concentration. After drying the three kinds of wastewater sludge at oil temperatures 160 degrees C for 10 min, it was found that the water content in the sludge from the chemical, leather, and plating plants reduced from 80.0 to 5.5%, 81.6 to 1.0%, and 65.4 to 0.8%, respectively. Furthermore, the heat values of the sludge from the chemical, leather, and plating plants prior to fry-drying were 217, 264, and 428 kcal/kg, respectively. After drying, these values of sludge increased to 5317, 5983 and 6031 kcal/kg, respectively. The heavy metals detected in the sludge after drying were aluminum, lead, zinc, mercury, and cadmium. Most importantly, if the dried sludge is used as a solid fuel, these heavy metals can be collected from the dust collector after combustion.
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http://dx.doi.org/10.1016/j.jhazmat.2009.02.053DOI Listing
August 2009

Removal of NO from flue gas by aqueous chlorine-dioxide scrubbing solution in a lab-scale bubbling reactor.

J Hazard Mater 2008 Feb 22;150(3):649-55. Epub 2007 May 22.

Department of Chemistry, A.I.J.H.M. College, Rohtak 124001, Haryana, India.

The present study attempts to clean up nitric oxide from the simulated flue gas using aqueous chlorine-dioxide solution in the bubbling reactor. Chlorine-dioxide is generated by chloride-chlorate process. Experiments are carried out to examine the effect of various operating variables like input NO concentration, presence of SO(2), pH of the solution and NaCl feeding rate on the NO(x) removal efficiency at 45 degrees C. Complete oxidation of nitric oxide into nitrogen dioxide occurred on passing sufficient ClO(2) gas into the scrubbing solution. NO is finally converted into nitrate and ClO(2) is reduced into chloride ions. A plausible reaction mechanism concerning NO(x) removal by ClO(2) is suggested. DeNO(x) efficiency increased slightly with the increasing input NO concentration. The presence of SO(2) improved the NO(2) absorption but pH of solution showed marginal effect on NO(2) absorption. NO(x) removal mechanism changed when medium of solution changed from acidic to alkaline. A constant NO(x) removal efficiency of about 60% has been achieved in the wide pH range of 3-11 under optimized conditions.
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http://dx.doi.org/10.1016/j.jhazmat.2007.05.016DOI Listing
February 2008

A novel process for CO2/CH4 gas separation on activated carbon fibers--electric swing adsorption.

J Colloid Interface Sci 2006 Jun 20;298(2):523-8. Epub 2006 Feb 20.

Clean Energy Research Department, Korea Institute of Energy Research, P.O. Box 103, Yusong-gu, Daejeon 305-600, South Korea.

Equilibrium and breakthrough adsorptions on activated carbon fibers (ACF) were conducted for CO2 and CH4 gas mixtures and the selective separation of CO2 was demonstrated. An electric swing adsorption process (ESA) was exploited to effect the rapid desorption of adsorbed gas at atmospheric pressure. Also, the relationship between the electrical behavior and desorption characteristics of ACF is discussed. In a single component adsorption experiment, the amount of adsorbed CO2 reached up to 40 mg/g-ACF, twice as much as that of adsorbed CH4. Therefore, the separation factor, defined as the ratio of adsorbed CO2 to adsorbed CH4, was 2.0. Multicomponent experiments showed a higher separation factor of 5.2, owing to a roll-up phenomenon. The temperature increase is not linearly proportionate to the power input, while the passage of higher electrical voltage (30 V) caused the ACF temperature to exceed 200 degrees C within 30 s. CO2 desorption at low voltage was well accomplished by heating the ACF to temperatures <60 degrees C. An ACF adsorption bed regenerated with ESA showed a constant regeneration efficiency of over 85% with a regular breakthrough curve. The ESA method increased desorption efficiency by over 20%, compared with the vacuum method.
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http://dx.doi.org/10.1016/j.jcis.2005.12.052DOI Listing
June 2006
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